Primary drive chain housing



FIG. 1 is a front perspective view of the primary drive chain housing showing the new design thereof;

FIG. 2 is a front perspective view thereof as seen from the bottom;

FIG. 3 is a front elevational view thereof;

FIG. 4 is a left side elevational view thereof;

FIG. 5 is a right side elevational view thereof;

FIG. 6 is a bottom elevational view thereof;

FIG. 7 is a top elevational view thereof; and,

FIG. 8 is a rear elevational view thereof.

The broken lines showing various other features of the primary drive chain housing throughout FIGS. 1 through 8 are for illustrative purposes only and form no part of the claimed design. 

The ornamental design for a primary drive chain housing, as shown and described. 